Category Archives: Astrochemistry

Ultima Thule

The end of 2018 and new year was full of space research news. In a very short time the Japanese Hayabusa2 touched an asteroid, the New Horizons spacecraft reached the Kuiper belt object Ultima Thule, and the Chinese probe Chang’e landed the Jade Rabbit 2 rover in the far side of the moon. The flyby of Ultima Thule is particularly interesting considering the distance of 6500 millions of km (equivalent to a radio attenuation of 303 dB at 7 GHz) and the fact that it was reached with about 35% of the remaining hydrazine fuel. New Horizons is expected to head towards another Kuiper object in the next years.

Two NASA images of Ultima-Thule taking in January 2019.
The Chinese lander on the far side of the moon.

COMs in Enceladus

An article in Nature reported the observation of astrophysically complex organic molecules (COMs) in cryo plumes ejected from the interior water ocean of Enceladus, one of Saturn satellites. The composition of the plumes was detected using mass spectrometry during a flyby of the spacecraft Cassini, before it was destroyed in 2017. Most of ice particles ejected from Enceladus are almost pure water, but a 1% is rich in organic molecules, some of them up to 200 amu. These results are the first evidence of complex organics from an extraterrestrial water ocean. The identity of these organic compounds is not clear, but they could contain carbon (C7 to C15), oxygen and eventually nitrogen. A prominent peak was associated to cationic forms of the benzene ring. Enceladus seems the only member of the solar system with a water ocean, an internal energy source and complex organics, apart from our planet.

Engineers Plan to Build Instrument to Study the Plumes of Enceladus

Picture Credits: NASA/JPL-Caltech/Southwest Research Institute


The European (ESA-Roscosmos) ExoMars Trace Gas Orbiter finished aerobraking dives and started taking data last April, 28. The Orbiter will specially check methane composition to discern if the  gas originated from geological or possible biological sources. The probe includes several ultraviolet and infrared spectrometers. The combination of mid-, near- and far-infrared spectra will provide identification of several atmospheric gases (H2O, O2, CO2, SO2, HF, HCl, etc).

In the picture below the Korolev crater, one of the first images from the orbiter.

Aromatics in space

Benzonitrile has been detected in the interstellar medium, as reported in Science. The interest of this aromatic molecule is the possibility of calculating the abundance of benzene from which it was generated, together with the growing interest to indentify the carriers of polycyclic aromatic hydrocarbons and polycyclic aromatic nitrogen heterocycles. The report is introduced by Joblin and Cernicharo in the same issue. An updated list of molecules found in the space can be obtained from the Institut of Physics at the University of Cologne. In the picture below the Green Bank telescope. Related to this, Nature informs that the Arecibo telescope was saved from being dismantled thanks to a mistery funder.